Lithium Abundances and Rotational Behavior for Bright Giant Stars�,

Home , Bright giant, HD 180262, HD 63032, HD 70555

A&A 450, 1173–1179 (2006) Astronomy DOI: 10.1051/0004-6361:20053485 & c ESO 2006 Astrophysics

Lithium abundances and rotational behavior for bright giant stars,

A. Lèbre1,P.deLaverny2, J. D. do Nascimento Jr.3, and J. R. De Medeiros1,3

1 Groupe de Recherche en Astronomie et Astrophysique du Languedoc, UMR 5024/ISTEEM (CNRS), Université de Montpellier II, Place Bataillon, 34095 Montpellier, France e-mail: [email protected] 2 Observatoire de la Côte d’Azur, Département Cassiopée, UMR 6202 (CNRS), BP 4229, 06304 Nice, France 3 Departamento de Física, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN, Brazil

Received 20 May 2005 / Accepted 16 November 2005 ABSTRACT

Aims. We study the links possibly existing between the lithium content of bright giant stars and their rotational velocity. Methods. We performed a spectral analysis of 145 bright giant stars (luminosity class II) spanning the spectral range from F3 to K5. All these stars have homogeneous rotational velocity measurements available in the literature. Results. For all the stars of the sample, we provide consistent lithium abundances (ALi), effective temperatures (Teff), projected rotational velocity (v sin i), mean metallicity ([Fe/H]), stellar mass, and an indication of the stellar multiplicity. The gradual decrease in lithium abundance with Teff is confirmed for bright giant stars, and it points to a dilution factor that is at least as significant as in giant stars. From the F to K spectral types, the ALi spans at least three orders of magnitude, reflecting the effects of stellar mass and evolution on dilution. Conclusions. We find that the behavior of ALi as a function of v sin i in bright giant stars presents the same trend as is observed in giants and subgiants: stars with high ALi are moderate or fast rotators, while stars with low ALi show a wide range of v sin i values.

Key words. stars: abundances – stars: atmospheres – stars: evolution – stars: rotation

1. Introduction detection to the current interstellar medium and meteoritic observed value of about 3.2 dex. After a sudden decline around Lithium is a key element in the study of the chemical evolu- the referred spectral types, the abundances of lithium pro- tion of the Galaxy, as well as in understanding the evolutionary gressively decrease with effective temperatures once the stars history of stars, due particularly to its role as an important diag- evolve along the spectral types G to K. Qualitatively, such be- nostic of internal stellar mixing. In recent years, there has been havior reflects the dilution of surface lithium by convective a tremendous upsurge in the observational study of the stellar mixing as a consequence of the development of the convective ff lithium line at 6707.81 Å in field stars at di erent regions in the envelope toward the inner and hotter stellar regions, where Li Hertzsprung Russel diagram. The behavior of Li abundances as is expected to be destroyed rapidly by (p, α) reactions at tem- ff a function of e ective temperature is now well-established for peratures >2.4 × 106 K. Thus, subgiant and giant stars evolv- both subgiant stars (De Medeiros et al. 1997; Lèbre et al. 1999; ing into the G and K spectral types are expected to have low Randich et al. 2000; Mallik et al. 2003) and giant stars (Brown lithium abundances. Moreover, theoretical models predict that et al. 1989; Wallerstein et al. 1994; De Medeiros et al. 2000; surface lithium has to be diluted by a factor of 28 to 60 in stars de Laverny et al. 2003). of 1–9 M at the bottom of the red giant branch (Iben 1965, These studies have shown, in the broadest sense, two clear 1966a,b, 1967). distinct features in the distribution of Li abundances (ALi) along the spectral regions F, G, and K. Single subgiants and gi- After this stage, no additional convective dilution should ants bluer than the ones of the spectral types F8 and G0, re- occur. Nevertheless, the observational behavior of ALi shows that the dilution factor is far more important than the stan- spectively, present a wide dispersion in ALi from about null dard theoretical predictions, with values as high as 1000 within Based on observations collected at ESO, La Silla, Chile, and at the giant region (Brown et al. 1989; De Medeiros et al. 2000). the Observatoire de Haute Provence, France, operated by the Centre This fact points to additional mixing mechanisms operating in National de la Recherche Scientifique (CNRS). evolved stars. From different studies (e.g.: Brown et al. 1989; Table 1 is only available in electronic form at Fekel & Balachandran 1993; Drake et al. 2002) there is now a http://www.edpsciences.org growing list in the literature of single G- and K-type giant stars

Article published by EDP Sciences and available at http://www.edpsciences.org/aa or http://dx.doi.org/10.1051/0004-6361:20053485 1174 A. Lèbre et al.: Li abundances and rotation for bright giants that violate this general rule, exhibiting ALi far in excess of the of rotational and radial velocities by De Medeiros & Mayor predicted values. The root-cause for such unexpected behavior (1999). Let us recall that this work compiles precise rotational is not understood clearly. velocity v sin i and signatures of either single or binary behav- In addition to the behavior of lithium versus effective tem- ior for a large and homogeneous sample of about 430 bright gi- perature, the relationship between ALi and the rotational ve- ants. The rotational velocities measured by these authors have − locity in subgiant and giant stars has been studied by differ- an uncertainty of about 2.0 km s 1 for stars with a v sin i lower − ent authors (Wallerstein et al. 1994; De Medeiros et al. 1997, than about 30.0 km s 1. For faster rotators, the estimations in- 2000; do Nascimento et al. 2000, 2003; de Laverny et al. dicate an uncertainty of about 10% on the measurements of 2003; Mallik et al. 2003). In spite of the fact that fast rota- v sin i. tors present enhanced lithium content, the connection rotation- Stars in our observational sample were selected to cover the ff lithium seems to be more complex and to depend on di er- spectral range from F3 to K5 in the luminosity class II. Such a ent stellar parameters. Slow rotators, e.g. typically giants and −1 selection ensures that we can focus on 3 regions: (i) the region subgiants with v sin i lower than about 10.0 km s ,showa where bright giants present a broad range in values of rotational wide range of ALi values with at least 3 mag of dispersion velocity (the F-type stars), (ii) the region of the discontinuity (De Medeiros et al. 2000; do Nascimento et al. 2003; de in rotation (the late F-type/early G-type stars), and (iii) the re- Laverny et al. 2003). Such dispersion apparently depends on gion of the slow rotators (the G- and K-type stars). Table 1 stellar mass (De Medeiros et al. 2000). lists the 145 program stars in order of increasing HD num- For stars of higher luminosity classes, namely for bright ber, with the respective projected rotational velocity v sin i from giants and supergiants, previous investigations of the behavior De Medeiros & Mayor (1999) and the stellar parameters de- of lithium and its connection to rotation have been hampered rived from the spectroscopic study (see next section). by the paucity of data. Luck & Wepfer (1995) have analyzed the behavior of ALi for a sample of 38 field bright giants of spectral types F, G and K. In spite of the limitation of their 2.2. Spectroscopic observations sample composed of 13 F-type, 22 G-type, and 3 K0 bright giants, these authors have observed, for this luminosity class, The data were acquired during three observational runs in the well-known gradual decrease in ALi with effective temper- August 1997, February 1998, and July 2003 for northern stars, ature established for other luminosity classes. Luck & Wepfer and in November 1997 for southern stars. We used three dif- (1995) have also found that Li depletions for bright giants are ferent telescopes and instrumentations to observe the spec- more severe than theoretical predictions with a dilution factor tral region around the lithium line at 6707.81 Å. For north- between 100 and 1000. ern stars, high-resolution spectra of the lithium region were With the main goal of settling the question of the be- acquired with the AURELIE spectrograph (Gillet et al. 1994) havior of lithium and its connection to rotation in evolved mounted at the 1.52 m telescope of the Observatoire de Haute intermediary-mass stars, we here present a spectroscopic study Provence (OHP, France). The spectrograph used a cooled of the lithium line at 6707.81 Å for a large sample of bright 2048-photodiode detector forming a 13 µm pixel linear array. giants with spectral types from middle F to middle K. For A grating with 1800 lines/mm was used, giving a mean dis- all these stars, precise radial and rotational velocity measure- persion of 4.7 Å/mm and a resolving power around 45 000 (at ments (vrad and v sin i) are available from De Medeiros & Mayor 6707 Å). For this instrument and the selected set-up, the spec- (1999). The combination of our spectroscopic data with these tral coverage was about 120 Å. The signal-to-noise ratio was v sin i measurements allows an unprecedented analysis of the always better than 50. In July 2003, complementary spectra connection rotation-lithium for intermediate-mass bright giant (mainly of F type bright giant stars) were collected with the stars. Furthermore, this set of data (ALi and v sin i measure- ELODIE spectrograph mounted at the 1.93 m telescope of the ments) is used for the study of possible links to the other prop- OHP (Baranne et al. 1996). Very similar instrumental condi- erties of bright giant stars, such as metallicity, stellar mass, and tions were used (resolving power of 42 000 and signal-to-noise binarity. In the next section (Sect. 2) we present our program ratio better that 50). sample and the spectroscopic observations we have collected. For southern stars, high-resolution spectra were acquired Section 3 describes the chemical analysis performed on our with the Coudé Echelle Spectrometer (CES) in the long cam- 145 bright giants in order to derive their stellar parameters and era mode (Kapper & Pasquini 1996), mounted at the 1.44 m Li abundances. The main conclusions on the Li behavior along CAT telescope, at La Silla, ESO. An RCA high resolution CCD rotational velocity, effective temperature, indication of bina- with 640 × 1024 pixels was used as the detector with a pixel rity, and stellar evolution are finally drawn in the last section size of 15 × 15 µm. The dispersion was around 1.9 Å/mm and (Sect. 4). the resolving power was about 95 000 (at 6707 Å). The spectral coverage for this instrument was about 70 Å and the signal-to- 2. Data description noise ratio was always better than 80. 2.1. The working sample For all the observational runs, thorium lamps were observed before and after each stellar observation for wavelength For the present study, we composed our observational sample calibration, whereas 3 series of flat-field using an internal lamp from a selection of 145 F, G and K bright giants in the catalog of tungsten were obtained during each night of observation. A. Lèbre et al.: Li abundances and rotation for bright giants 1175

Table 2. Comparison of measured ALi and fundamental parameters for 18 program stars in common with Luck & Wepfer (1995). While for these stars our measured values are listed in Table 1, the present table displays the atmospheric parameters and Li abundances (ALi) spec- troscopically derived by Luck & Wepfer (1995). The differences in Teff (∆Teff )andinALi (∆ALi) present rms of 100 K and 0.35 dex, respectively. No value (–) in the column ∆ALi means that we derived upper limit in ALi in agreement with the value reported in Luck & Wepfer (1995).

HD Teff log g [Fe/H] ALi ∆ALi ∆Teff 1227 5075 2.7 0.05 0.76 >0.36 –25 27022 5275 2.6 0.05 1.25 0.35 5 65228 5900 1.7 0.16 2.52 0.4 –300 67447 4825 1.5 –0.08 1.15 0.05 –175 68752 4725 0.8 –0.14 <–0.23 – 25 71115 5050 2.2 –0.03 0.80 >0.4 –100 Fig. 1. Lithium spectral region for four program stars that present 76219 4875 1.9 0.00 0.31 – –125 moderate to high Li abundances. In each panel, the observed spec- 76494 4900 2.0 0.01 1.00 0.60 –50 trum is the dotted line, while the thin line indicates the synthetic spec- 109379 5125 2.2 0.02 1.03 0.13 –25 trum computed with the stellar parameters mentioned in Table 1 for i 129989 4800 2.2 0.16 –0.03 – 0 the relevant star. The Li 6707.81 Å line is indicated with a short 150030 4775 1.9 0.03 0.26 – –125 vertical line. 161149 6650 3.0 0.42 2.27 >0.27 30 173009 4500 1.0 –0.30 –0.09 – 0 180809 4500 1.6 0.09 0.07 – 0 Flat-field corrections and wavelength calibrations were per- 195295 6525 1.9 0.05 1.84 >0.34 –75 formed using the MIDAS package. 197177 5150 2.3 0.47 1.37 0.47 0 214567 5050 2.5 –0.11 <–0.26 – –50 216756 6725 3.9 –0.09 3.05 –0.05 75 3. Stellar parameters and lithium abundances 3.1. Adopted methodology As already discussed by Lèbre et al. (1999), the major For our present spectroscopic analysis and in order to stay con- source of uncertainty for this abundance analysis comes from sistent with our previous works, we derived LTE lithium abun- errors in the determination of the Teff. We estimated that effec- dances (ALi) from the resonance line at 6707 Å using the spec- tive temperatures, issued from synthetic spectra, were derived trum synthesis method (see Lèbre et al. 1999; and Jasniewicz with a smaller uncertainty than ±200K.Thisleadstoaner- et al. 1999, for more details). To compute the most appropri- ror of less than 0.2 dex on the derived metallicities and lithium ate synthetic spectra to fit the observations, a first guess for the abundances. stellar parameters of our list of bright giants was estimated. We thus looked into the literature to find effective tempera- 3.2. Comparison of our measured ALi to previous tures (T ff), gravities (log g), and often metallicities ([Fe/H]), e studies mainly in Cayrel de Strobel et al. (2001), in Allende Prieto & Lambert (1999), and in Alonso et al. (1999). For sample stars There is up to now only one study in the literature that without any published stellar parameters, we first estimated Teff is fully devoted to lithium abundances in intermediate-mass, from (B − V) color index (Flower 1996) and set log g = 2.0, a evolved stars including bright giants (Luck & Wepfer 1995). − microtuburlence velocity of 2 km s 1 and [Fe/H] = 0.0, those Nevertheless, this study is based on a limited sample of values being commonly adopted for Pop. I giant stars. 38 bright giant stars. Fundamental parameters and ALi values Synthetic spectra were then computed from these stellar pa- were derived by these authors following a synthesis proce- rameters and with v sin i from De Medeiros & Mayor (1999). dure based on MARCS models, then comparable to the pro- We used the same line list and model atmospheres as described cedure we have adopted here. Hence we present a compari- in Lèbre et al. (1999) and in Jasniewicz et al. (1999). The stel- son of the derived parameters for 18 stars common to both lar parameters of all the bright giants (mainly Teff,[Fe/H], and programs. As shown in Table 2 our data agree rather well log g) were then corrected, when necessary, in order to improve with those from Luck & Wepfer (1995), considering the er- the fit quality of the several Fe I and other metallic lines found ror bars in both works. In this context, both data sets ide- in the observed spectral range (∼120 Å) centered on the Li line ally complement each other from the blue to the red spec- feature. The final adopted stellar parameters and the derived Li tral regions. The difference in Teff computed for the 18 stars abundances are presented in Table 1 (online material) for all presents a rms of 100 K. The difference in ALi has been com- the stars of our sample. For four selected stars, in Fig. 1, we puted only for Li detection in both works (11 stars among 18), present their spectra in the Li region (observation and the best thereby excluding upper limits on ALi.Itpresentsanrms fit as synthetic spectrum). of 0.35 dex. For individual cases, however there are some 1176 A. Lèbre et al.: Li abundances and rotation for bright giants

4.0 puzzling differences in Teff (HD 65228, explaining entirely its disagreement on ALi), in [Fe/H] (HD 27022, HD 197177), or in ALi (HD 76494, HD 161149). For those last two stars, the 3.0 difference in ALi clearly comes from the adopted v sin i values in both works. Indeed, Luck & Wepfer (1995) used fairly inaccurate and non-homogeneous v sin i values (coming from 2.0 the Bright Stars Catalogue, or not even determined for a few stars), while our synthetic spectra are computed with highly ac- A_Li curate v sin i values obtained from CORAVEL measurements 1.0 (De Medeiros & Mayor 1999). For the 18 common stars, we then computed synthetic spectra with atmospheric parameters,

Li content, and v sin i values as presented in Luck & Wepfer 0.0 (1995). They clearly failed to match our own observations and their Li feature, mainly due to a deficiency of the line broad- 7000 6000 5000 4000 3000 ening in the synthetic spectra. Thus we feel more confident of Teff (K) our own determination of atmospheric parameters and ALi (as Fig. 2. Lithium abundances versus effective temperature. Single and presented in Table 1). binary stars are indicated with open and filled symbols, respectively. Triangles and circles refer to our present Li analysis, triangles being for Li upper limits, while circles are for Li abundance determinations. 4. Results and discussion Effective temperatures were derived with a smaller uncertainty than In addition to the unprecedented list of precise lithium abun- 200 K, leading to an error of less than 0.2 dex on lithium abundances. dances for 145 bright giant stars along the spectral range F, G, and K, the present work offers a unique possibility to study the lithium content in intermediate-mass, evolved stars of population I and its link with relevant stellar parameters. of our sample stars, their absolute magnitudes were first calcu- lated from V magnitudes and parallaxes given in the Hipparcos catalog (Perryman et al. 1997) available at SIMBAD/CDS. 4.1. Lithium abundance versus effective temperature Then the stellar luminosities were derived from these absolute

For the analysis of ALi as a function of effective temperature, magnitudes using a bolometric correction (BC) interpolated be- we followed two different approaches: the standard one on the tween giants and supergiants as described in Flower (1996). We basis of the ALi versus Teff plan, and a second one based on the used evolutionary tracks at solar metallicity and mass range be- position of stars in the HR diagram. The latter is clearly more tween 1.5 to 9 M, taken from grids of stellar models provided solid, giving the behavior of ALi versus Teff as a function of by Schaller et al. (1992). Hence the mass of each bright giant mass. can be estimated with respect to these theoretical evolutionary Figure 2 shows lithium abundances as a function of tracks. Note that 6 stars listed in Table 1, but without available effective temperature for the bright giant stars of our sample HIPPARCOS parallaxes, have been excluded from these dia- (represented by circles and by triangles for upper limit mea- grams in order to ensure consistency in the estimation of the surements). In this figure (and also in subsequent ones) open evolutionary status of the largest part of our sample. symbols stand for single stars, whereas filled symbols indi- Figures 3 and 4 display such HR diagrams, indicating the cate binaries (or stars with variability in radial velocity). The lithium abundances and rotational velocity, respectively, where gradual decrease in lithium abundance with effective tempera- the effects of mass and evolution can be outlined. In these fig- ture for bright giant stars is solidly defined in Fig. 2, perhaps ures the symbol sizes are proportional to the values of rele- pointing to a dilution factor at least as important as in giants. vant parameters, respectively ALi and v sin i. The location of the Following the same trend observed in giant stars (De Medeiros turn-off is indicated with a dotted line, while the location of the et al. 2000; De Laverny et al. 2003), Fig. 2 shows that at a bottom of the red giant branch is indicated with a dashed line. given effective temperature, all along the F to K spectral types, From these figures a first important feature of the evolutionary the ALi spans about three orders of magnitude or more, reflect- status of the present sample should be underlined: the large ma- ing the effects of the evolutionary stage and stellar mass on jority of our sample stars is located in the mass range expected dilution (e.g.: Lambert et al. 1980; Brown et al. 1989). These for bright giants, which have masses from about 2.5 M to features are clearly observed in Fig. 3, where mass and evolu- 9 M, although a few stars are found with smaller masses than tionary effects are taken into consideration (see next section). about 2 M. Although these objects are classified in the litera- The absence of stars in the Teff interval from 5500 K to 6500 K ture as bright giants, they are clearly rather evolving around the corresponds to the Hertzsprung gap. turn-off or at the main sequence. Another important point con- cerns the evolutionary status of the bright giants, namely those stars with masses larger than about 2.5 M: stars with effective 4.2. Lithium abundance in the Teff– luminosity diagram temperature smaller than about 5000 K (or log(Teff) < 3.7) may We turn now to the analysis of the ALi behavior in the be found on different evolutionary stages, evolving either in the Teff versus luminosity diagram. To infer the evolutionary status first crossing on the giant branch or evolving along blue–loops. A. Lèbre et al.: Li abundances and rotation for bright giants 1177

5.0

4.0 7M

5M 3.0 4M

3M log(L/L ) 2.0 2.5M

2M 1.0 A_Li < 1.4 (upper limit) 1.7M A_Li < 1.4 (measurement) 1.5M A_Li < 2.0 (upper limit) A_Li > 1.4 (measurement) 1.25M

4.00 3.80 3.60 3.40 log(Teff)

Fig. 3. Hertzsprung-Russell diagram of our program stars with evolutionary tracks from Schaller et al. (1992). The location of the turn-off is indicated with a dotted line, while the location of the bottom of the red giant branch is indicated with a dashed line. Single stars and binaries are represented by open and filled symbols, respectively. Indication of the lithium abundances (ALi) is given through two different symbol sizes (ALi inf./sup. to 1.4 dex). Upper limits on ALi are also indicated with open/filled triangles. See text (Sect. 4.2) for more details.

5.0

4.0 7M

3.0 4M

3M log(L/L ) 2.0

2.5M

2M 1.0 Vsini < 10 km/s 1.7M 10 < Vsini < 40 km/s 1.5M Vsini > 40 km/s 1.25M

4.00 3.80 3.60 3.40 log(Teff)

Fig. 4. Same as Fig. 3, but the symbol sizes refer to rotational velocity (as indicated in the legend frame). Again, binaries are represented by ﬁlled symbols.

From Fig. 3, we notice that the low mass stars (namely the turn-oﬀ) show a wide range in Ali, from about the cos- stars with M < 2 M), present the expected behavior for mic value ALi ∼ 3.2, to abundances lower than 0.0., whereas their Ali: stars located in the F spectral region (those around stars along the G to K spectral range, except for a very few 1178 A. Lèbre et al.: Li abundances and rotation for bright giants

4.0 ALi moderate values, present essentially low lithium content. For typical bright giants (i.e., stars in the mass range 2.5 M to 9 M), the ALi behavior follows – at least qualitatively – the same feature as has already been observed for giant and sub- 3.0 giant stars (De Medeiros et al. 2000; De Laverny et al. 2003; do Nascimento et al. 2000). There is indeed a trend to a large range of ALi values among stars located on the blue side of 2.0 the Hertzsprung gap, while the large majority of stars on the A_Li red side (namely in the G to K spectral regions) presents essentially low Li abundances. Moreover, in this latter spectral 1.0 region, single and binary stars seem to follow the same behavior. Brown et al. (1989) have shown that giant stars with average masses around 1.2 M have average ALi < 0.0, corre- 0.0 sponding to 1.5 dex less than abundances predicted by stan- 0.0 20.0 40.0 60.0 80.0 dard theory. The present work shows the same striking feature V sini (km/s) among giant stars with larger masses than about 2 M. Indeed ∼ ∼ Fig. 5. Lithium abundances versus rotational velocity. Single and bi- 70% of our sample stars show ALi < 0.4, and 40% even show nary stars are indicated with open and filled symbols, respectively. ALi < 0.0. Following the similar analysis undertaken by Brown Triangles and circles refer to our Li abundance determinations, tri- et al. (1989), we found that Li abundance correlates poorly with angles being for ALi upper limits. We estimated the error on lithium the mass of bright giant stars. abundances of less than 0.2 dex. The rotational velocities have an −1 Despite these clear results, determination of the Li dilution uncertainty of about 2.0 km s for low and moderate rotators (v sin i −1 factor for the bright giant stars is not an evident task. As we lower than about 30.0 km s ) while for fast rotators, the estimations have underlined, stars with effective temperature that is smaller indicate an uncertainty of about 10% on the measurements of v sin i. than about 5000 K are in different evolutionary stages, even if they have well-developed convective envelopes. As shown around F9II (De Medeiros 1989). In Fig. 4, this feature is again by different authors (e.g.: do Nascimento et al. 2003) after clearly observed for our sample of stars. Indeed, binary and the F-late type spectral region, corresponding to effective tem- single stars that are hotter than ∼5200 K show a wide range of peratures that are smaller than about 5000 K, the develop- rotational velocity, with v sin i ranging from low to moderate ment in mass of the convective envelope arises very rapidly. and to high rotators, while on the cooler side of the discontinu- For the stars evolving on the first crossing, convective dilu- ity, except for a few moderate rotators with v sin i between 10 tion associated with some extra-mixing process is expected − and20kms 1, single and binary stars present essentially low to represent the main root-cause to explain the observed low − v sin i (v sin i < 10 km s 1). A abundances. Nevertheless, for stars evolving on the blue- Li Finally, Fig. 5 shows the behavior of A as a function of loops one may expect a more complex status. Certainly, these Li v sin i. For the first time, it is then possible to establish this stars have experienced mixing, even quite deeply, and their pri- behavior on a large sample of bright giants with homoge- mordial surface Li content should be as diluted so as in stars on neous and high precision v sin i measurements. Indeed, we have the first crossing or more. In addition, mass-loss in stars evolv- strictly limited the representation of Fig. 5 to our program stars ing along the loops is expected to be more severe than in giants in order to ensure the homogeneity of the displayed data: v sin i on the first crossing. This process should also play a role in the values from CORAVEL measurements and A determinations increase of Li content at the stellar surface. In this context, the Li from our present spectroscopic study. The same trend already Li dilution factor strongly depends on the evolutionary status observed for giant and subgiant stars (De Medeiros et al. 2000; of the stars. De Laverny et al. 2003; do Nascimento et al. 2000) is present However an additional interesting point in the present sur- here: stars with high ALi (ALi > 2.0 dex) are moderate or fast ro- vey is the apparent lack of lithium-rich bright giant stars, typ- −1 tators (v sin i > 10 km s ), whereas for low ALi there is a large ically single late G- and K-type stars with ALi as large as the spread in the values of v sin i. Nevertheless, two fast rotators, cosmic lithium abundance value. In spite of this fact, few bright HD 161149 and HD 168393 seem to stand out of such a trend, giants present a moderate content of lithium. Two binaries, presenting rather low Li content. These stars appear to have no HD 34579 and HD 77996, and two single stars, HD 41927 particularity, except the fact that, in the context of the present and HD 98217, are all low rotators and, in the spectral type sample, they are rather low mass stars evolving near the turn- range G8II to K2II, show slightly enhanced Li content, with off. ALi ∼ 1.5 dex.

5. Conclusions 4.3. Lithium abundance versus rotational velocity In this work, we present an unprecedented list of precise stel- For bright giants, the distribution of their v sin i values as a lar parameters and lithium abundances for 145 bright stars function of effective temperature presents a sudden disconti- ranging along the spectral types F, G, and K, the large major- nuity around Teff ∼ 5200 K, corresponding to the spectral type ity of them genuine bright giants, inferred from spectroscopic A. Lèbre et al.: Li abundances and rotation for bright giants 1179 analysis based on MARCS models. This study of lithium con- Acknowledgements. This work was supported by continuous grants tent in intermediate-mass, evolved stars of Population I (i.e., from CNPq Brazilian Agency, by a PRONEX grant of the with stellar mass ranging from 2.5 M to 9 M) complements FAPERN Rio Grande do Norte Agency, and by financial resources the only work ever produced on bright giants (Luck & Wepfer from the French CNRS/INSU Programme National de Physique 1995) and also similar studies devoted to lower luminosity class Stellaire (PNPS). J.D.N.Jr acknowledges the CNPq Brazilian sup- / / stars: subgiants (Lèbre et al. 1999; do Nascimento et al. 2000) port CNPq PROFIX 540461 01-6. The authors warmly thank Dr. G. Wallerstein for his fruitful comments on the paper. This research has and giants (De medeiros et al. 2000; De Laverny et al. 2003). ff made use of the SIMBAD database, operated at the CDS (Strasbourg, Considering the behavior of ALi as a function of e ective France), and of NASA’s Astrophysics Data System. temperature, the gradual decrease in lithium abundance with effective temperature is again well-established for bright giant stars, pointing to a dilution factor that is at least as important References as in giants. This behavior follows the same trend already ob- Allende Prieto, C., & Lambert, D. L. 1999, A&A, 352, 555 served in giant and subgiant stars: at a given effective temper- Alonso, O., Arribas, S., & Martìnez-Roger, C. 1999, A&AS, 139, 335 ature, all along the F to K spectral types, the ALi spans at least Baranne, A., Queloz, D., Mayor, M., et al. 1996, A&AS, 119, 373 three orders of magnitude, reflecting the effects of evolutionary Brown, J. A., Sneden, C., Lambert, D. L., & Dutchover, E. 1989, ApJ, status and stellar mass on dilution. 71, 293 For single stars, as well as for binaries, there is also a large Cayrel, G., Soubiran, C., & Ralite, N. 2001, A&A, 373, 159 De Laverny, P., do Nascimento, J. D. Jr., Lèbre A., & De Medeiros, dispersion on ALi values for stars located on the blue side of the Hertzsprung gap, while almost all the stars located on the red J. R. 2003, A&A, 410, 937 side (G to K spectral type range) present low Li abundances. De Medeiros, J. R. 1989, Ph.D. Geneva Observatory De Medeiros, J. R., do Nascimento, J. D. Jr., & Mayor, M. 1997, A&A, This behavior follows the one found in previous works for gi- 317, 701 ants of smaller stellar masses. We show here that bright giant De Medeiros, J. R., & Mayor, M. 1999, A&AS, 139, 443 stars with larger masses than about 2.0 M have ALi < 0.0, cor- De Medeiros, J. R., do Nascimento, J. D. Jr., Sankarankutty, S., Costa, responding to at least 1.5 dex less than abundances predicted J. M., & Maia, M. R. G. 2000, A&A, 363, 239 by standard theory. We also found that Li abundance correlates do Nascimento, J. D. Jr., Charbonnel, C., Lèbre, A., De Laverny, P., & poorly with the mass of bright giant stars. While our survey De Medeiros, J. R. 2000, A&A, 357, 931 points to an apparent lack of lithium-rich stars (typically single do Nascimento, J. D. Jr., Cantos Martins, B. L., Melo, C. H. F., late G- and K-type stars, with ALi as large as the cosmic value), Porto de Mello, G., & De Medeiros, J. R. 2003, A&A, 405, 723 we detected, however, four genuine bright giants (low rotators Drake, N. A., de La Reza, R., da Silva, L., & Lambert, D. L. 2002, AJ, and in the spectral type range G8II to K2II), showing enhanced 123, 2703 Li content (with A ∼ 1.5 dex). Fekel, F. C., & Balachandran, S. 1993, ApJ, 403, 708 Li Flower, P. J. 1996, ApJ, 469, 355 Considering the behavior of A as a function of rotational Li Gillet, D., Burnage, R., Kolher, D., et al. 1994, A&AS, 108, 181 velocity, we find the same trend for our sample of bright giants Iben, I. J. 1965, ApJ, 142, 1447 that has already been observed for giant and subgiant stars: Iben, I. J. 1966a, ApJ, 143, 483 stars with high ALi are moderate or fast rotators, while stars Iben, I. J. 1966b, ApJ, 143, 505 with low ALi present a large spread in the values of v sin i. Iben, I. J. 1967, ApJ, 147, 624 Finally, the present work indicates that some related obser- Jasniewicz, G., Parthasarathy, M., de Laverny, P., & Thèvenin, F. 1999, vational programs should be undertaken in order to have a more A&A, 342, 831 solid understanding of the Li behavior in evolved stars from Kapper, L., & Pasquini, L. 1996, CAT+CES Operating Manual, ESO low to intermediate masses. First, the determination of Li abun- report, 3P6CAT-MAN-0633-0001 dances for a large sample of stars evolving at and immediately Lambert, D. L., Dominy, J. F., & Sivertsen, S. 1980, ApJ, 235, 114 after the turn-off – in particular for intermediate mass stars – Lèbre, A., De Laverny, P., De Medeiros, J. R., Charbonnel, C., & Da Silva, L. 1999, A&A, 345, 936 will help us quantify the level of Li content in stars leaving Luck, R. E., & Wepfer, G. G. 1995, AJ, 110, 2425 the main sequence. Secondly, the determination of Li content Mallik, S. V., Parthasarathy, M., & Pati, A. K. 2003, A&A, 409, 251 in G and K supergiants is also welcome, because it will be pos- Perryman, M. A. C., Lindegren, L., Kovalesky, J., et al. 1997, A&AS, sible to enlarge the present available sample of evolved stars. 323, 49 Thirdly, the determination of carbon isotope ratios in G and Randich, S., Pasquini, L., & Pallavicini, R. 2000, A&A, 356, L25 K giant and bright giant stars is an additional required step, Schaller, G., Schaerer, D., Meynet, G., & Maeder, A. 1992, A&AS, since this ratio is a very sensitive diagnostic of stellar evolu- 96, 269 tion. All these data are of fundamental importance for further Wallerstein, G., Bohm-Vitense, E., Vanture, A. D., & Gonzalez, G. understanding the Li dilution once stars of low to intermediate 1994, AJ, 107, 2211 masses leave the main sequence and begin the ascent to the red giant branch. A. Lèbre et al.: Li abundances and rotation for bright giants, Online Material p 1

Online Material A. Lèbre et al.: Li abundances and rotation for bright giants, Online Material p 2

Table 1. List of our 145 program stars with their main parameters. The (B − V), vrad, v sin i, and binarity index are from De Medeiros & Mayor (1999), and Teﬀ,logg,[Fe/H], and ALi are from our chemical analysis based on synthetic spectra (see Sect. 3.1). Stars indicated with an asterisk ∗ ( ) have also been observed by Luck & Wepfer (1995) and comparisons on atmospheric parameters and ALi are discussed in Sect. 3.2. Stars indicated with such a symbol (−) are not included in Figs. 3 and 4 (HR diagrams) as there is no HIPPARCOS parallax available for these six objects (see Sect. 4.2).

Star Sp. B − V vrad v sin i Binarity Teﬀ log g [Fe/H] ALi Type km s−1 km s−1 K HD 936 G7.5II 1.12 0.14 8.1 sb 4900 2.0 –0.3 <0.4 HD 1227∗ G8II-III 0.92 0.30 1.0 – 5100 2.6 0.0 <0.4 HD 1367 K0II 0.94 –9.95 1.0 – 5150 2.0 0.0 <0.4 HD 1375 G8II 0.97 –0.45 1.0 – 5020 2.0 –0.2 <0.4 HD 4482 G8II 0.99 –5.11 1.0 sb 5040 2.0 –0.1 <0.4 HD 5418 G8II 0.96 5.03 1.0 – 5020 2.0 0.0 <0.4 HD 5848 K2II-III 1.21 7.89 1.0 – 4500 2.4 0.0 <0.0 HD 8681 K1II 1.12 –9.5 2.0 sb 4680 2.0 –0.4 <0.0 HD 11668 K0II 1.03 17.4 1.8 – 4800 2.0 –0.4 <0.0 HD 12409 G6II 0.91 6.0 – 5200 2.0 0.0 <0.4 HD 13280− K1/K2II 1.20 3.0 – 4570 2.0 –0.4 <0.0 HD 13611 G6II-III 0.88 –4.36 1.5 sb 5100 2.0 0.0 <0.4 HD 13640− K1/K2II 1.20 2.0 – 4570 2.0 –0.4 <0.0 HD 16735 K0II-III 1.12 –14.37 1.0 – 4820 2.0 –0.1 0.9 HD 16899 K0II 1.08 19.1 2.0 sb 4900 2.0 –0.5 <0.4 HD 17346 G9II 1.23 –7.00 2.7 – 4800 2.0 –0.3 <0.0 HD 18175 K0II 1.14 –34.67 <1.0 – 4680 3.0 –0.2 0.4 HD 20644 K2II-III 1.55 –3.92 1.4 sb 4150 2.0 0.0 <0.0 HD 21754 K0II-IIIFe 1.11 16.79 <1.0 sb 4700 2.6 –0.2 1.0 HD 21901 K1II 1.18 2.0 – 4570 2.0 –0.4 <0.0 HD 22287 G8II 0.97 33.0 2.0 – 4970 2.0 –0.4 <0.4 HD 24107 K1II 1.11 39.23 <1.0 – 4700 2.0 –0.4 <0.0 HD 25189 K2II-III 1.20 10.2 2.0 – 4600 2.0 –0.2 0.5 HD 25877 G8II 1.11 –13.03 4.5 – 4950 2.0 –0.1 <0.4 HD 26004 K0II-III 1.20 –12.1 2.0 – 4700 2.0 0.5 <0.0 HD 26045 K1II 1.14 2.0 – 4650 2.0 –0.2 <0.0 HD 26311 K1II-III 1.41 18.73 1.0 sb 4600 2.0 –0.2 1.2 HD 26673 G5II 1.01 –17.58 10.6 sb 4950 2.0 –0.1 <0.4 HD 27022∗ G5II 0.82 –19.75 1.0 – 5280 2.5 –0.2 0.9 HD 30031 K2/K3II 1.35 –15.9 1.9 – 4600 2.0 –0.3 0.6 HD 30504 K4II 1.45 –25.24 1.6 – 4100 2.0 –0.4 <0.0 HD 31398 K3II 1.49 17.38 3.8 – 4160 2.0 0.1 <0.0 HD 31767 K2II 1.37 14.85 1.1 – 4590 2.0 –0.3 1.0 HD 32068 K4II 1.15 –1.70 6.8 sb 4100 2.0 0.1 <0.0 HD 32356 K5II 1.38 –46.82 <1.0 sb 4100 2.0 –0.3 <0.0 HD 32406 K0II-III 1.21 15.07 3.0 – 4850 2.0 –0.3 1.0 HD 33239 G9II 1.09 –11.0 2.0 – 4760 2.0 0.5 <0.0 HD 34579 G8II-III 1.02 –52.05 <1.0 sb 4950 2.0 –0.2 1.5 HD 38871 K0.5II 1.04 11.7 1.8 sb 4900 2.0 –0.3 0.8 HD 39400 K2II 1.38 11.06 3.5 – 4250 1.5 –0.2 <0.0 HD 39632 G9II 1.40 12.17 7.8 – 4350 2.0 –0.1 <0.0 HD 40733 G8II 1.06 12.7 5.7 sb 4820 2.0 –0.4 <0.0 HD 40801 K0II 0.99 33.32 <1.0 – 5000 2.0 –0.3 <0.4 HD 41927 K2II-III 1.34 0.13 3.3 – 4650 2.0 0.0 1.5 HD 42351 K1II 1.35 –2.59 2.5 – 4500 2.0 –0.2 <0.0 HD 43335 K5II 1.56 42.95 2.1 – 4200 2.0 –0.2 <0.0 HD 45416 K1II 1.19 31.69 1.9 – 4500 2.0 –0.3 <0.0 HD 47475 K0II 1.15 14.3 5.5 – 4660 2.0 –0.3 <0.0 HD 49380 K3II 1.30 –16.91 <1.0 – 4500 2.0 –0.2 <0.0 HD 49778− G8II 1.04 0.8 2.0 – 5000 2.0 –0.4 <0.4 HD 50337 G6II 0.90 22.1 12.3 sb 4800 2.0 –0.4 <0.0 HD 50716− G6II 0.90 13.8 15.7 sb 5200 2.0 –0.2 <0.4 HD 51315− K0II 1.15 2.0 – 5100 2.0 –0.2 <0.4 HD 52938 K3.5II 1.71 5.36 3.9 – 4200 2.0 –0.1 1.1 A. Lèbre et al.: Li abundances and rotation for bright giants, Online Material p 3

Table 1. continued.

Star Sp. B − V vrad v sin i Binarity Teﬀ log g [Fe/H] ALi Type km s−1 km s−1 K HD 54519 K5II 1.51 13.5 5.7 sb 4200 2.0 –0.1 <0.0 HD 54825 K0II 1.06 42.11 <1.9 – 4900 2.0 0.0 <0.4 HD 55751 K2II 1.19 36.35 <1.0 – 4500 2.0 –0.3 0.2 HD 57146 G0II 0.96 30.4 9.9 – 5200 2.0 0.0 <0.4 HD 59878 K0II 1.00 33.82 <1.0 sb 5300 2.0 0.1 <0.4 HD 61772 K3II 1.54 –0.08 2.0 – 4000 2.0 –0.1 <0.0 HD 63032 K5II 1.71 16.3 8.3 sb 4200 2.0 –0.2 <0.0 HD 63870 K1II 1.11 –0.3 2.0 – 4800 2.0 –0.2 <0.0 HD 64067 G5II 1.12 19.12 7.6 sb 4700 2.0 –0.2 0.6 HD 64320 K0II 1.24 22.6 2.4 – 4490 2.0 –0.5 0.5 HD 65228∗ F7II 0.72 12.96 13.8 – 5600 3.0 0.0 2.1 HD 65662 K4II 1.55 23.8 2.3 – 4400 2.0 –0.4 1.2 HD 66812 G8II 1.01 13.9 10.6 – 4950 2.0 –0.4 <0.4 HD 67249 G5II 1.21 26.79 6.5 – 4700 2.0 –0.4 0.9 HD 67447∗ G7II 1.04 –11.64 4.4 – 5000 2.0 0.0 1.2 HD 68752∗ G5II 1.07 16.39 6.9 – 4700 2.0 –0.4 <0.0 HD 70555 K1II 1.42 31.8 3.8 – 4400 2.0 –0.3 <0.0 HD 71115∗ G7II 0.93 15.26 <1.2 sb 5150 2.2 –0.1 <0.4 HD 73155 K1.5II 1.30 4.1 3.1 – 4600 2.0 –0.4 <0.0 HD 76219∗ G8II-III 1.00 15.87 6.3 – 5000 2.0 –0.2 <0.4 HD 76494∗ G8II-III 1.00 –11.48 4.6 – 4950 2.0 <–0.3 0.4 HD 77250 K1II-III 1.11 32.70 1.6 – 4740 2.0 –0.2 <0.0 HD 77996 K2II-III 1.19 23.36 2.3 sb 4800 2.0 0.0 1.5 HD 79698 G6II 0.85 5.3 8.2 – 5310 2.0 –0.1 <0.4 HD 80126 G8II 1.04 14.7 3.8 – 4890 2.0 –0.4 <0.0 HD 87238 K1II 1.11 6.9 1.2 4900 2.0 –0.4 0.8 HD 88009 G8II 1.07 –19.11 <2.5 – 4820 2.0 –0.4 <0.0 HD 89388 K3II 1.54 8.2 5.5 – 4300 2.0 0.0 1.0 HD 89682 K3II 1.60 12.9 2.0 – 4300 2.0 –0.4 <0.0 HD 91942 K3.5II 1.60 9.4 5.8 – 3800 2.0 0.0 <0.0 HD 95725 K1II 1.05 –11.79 <1.0 – 4870 2.0 –0.1 <0.0 HD 98217 G8II 0.93 –15.36 2.0 – 5140 2.0 –0.2 1.5 HD 98839 G8II 1.00 –2.36 4.0 – 5010 2.1 0.0 <0.4 HD 106057 K0II-III 0.96 –26.30 <1.0 – 5100 2.0 –0.2 <0.4 HD 109379∗ G5II 0.89 –7.90 4.2 – 5150 2.0 –0.3 0.9 HD 119035 G5II 0.96 –19.43 <1.0 – 4900 2.0 –0.2 <0.4 HD 125728 G8II 0.92 29.48 <1.0 sb 5170 2.0 –0.3 <0.4 HD 129989∗,− K0II-III 0.97 –17.50 8.4 – 4800 2.2 0.0 <0.0 HD 130766 K3II 1.35 –13.81 1.0 sb 4400 2.0 –0.5 <0.0 HD 145931 K4II 1.46 –22.62 1.0 sb 4300 2.0 –0.3 <0.0 HD 148897 G8II 1.29 15.86 <1.9 sb 4400 1.5 –0.7 <0.0 HD 150030∗ G8II 1.04 –16.89 3.6 – 4900 2.0 –0.2 <0.4 HD 156283 K3II 1.44 –26.17 1.3 – 4130 1.7 –0.2 <0.0 HD 156681 K4II-III 1.54 38.76 1.0 – 4150 2.0 –0.3 <0.0 HD 157999 K2II 1.48 –28.38 4.2 sb 4300 2.0 0.0 0.4 HD 159181 G2II 0.95 –21.56 10.7 sb 5300 1.4 0.3 <0.4 HD 161149∗ F5II 0.43 –53.95 65.8 – 6620 2.0 ? <2.0 HD 168393 F5II 0.55 26.93 70.1 – 6000 2.0 ? <1.1 HD 171874 F6II 0.48 –48.93 17.7 – 6200 2.5 0.0 <1.1 HD 173009∗ G8II 1.11 –9.12 5.1 sb 4500 1.0 0.0 <0.0 HD 173764 G5II 1.09 –15.27 7.8 sb 4760 2.0 –0.2 <0.0 HD 174980 K0II-III 0.95 0.44 1.0 – 5150 2.0 0.1 <0.4 HD 177249 G5II 0.86 7.30 5.0 – 5100 2.3 0.0 <0.4 HD 180262 G8II-III 1.07 –25.59 1.4 – 5000 2.0 –0.3 <0.4 HD 180656 K1II 1.05 –46.84 1.0 – 4800 2.0 –0.3 <0.0 HD 180809∗ K0II 1.26 –28.02 3.5 – 4500 2.0 0.0 <0.0 A. Lèbre et al.: Li abundances and rotation for bright giants, Online Material p 4

Table 1. continued.

Star Sp. B − V vrad v sin i Binarity Teﬀ log g [Fe/H] ALi Type km s−1 km s−1 K HD 183912 K3II 1.09 –24.33 1.4 – 4270 2.0 –0.1 1.0 HD 184944 K0II-III 1.04 –45.31 1.0 sb 4210 2.0 0.0 0.6 HD 186155 F5II-III 0.43 –21.79 59.1 – 6000 3.0 0.0 3.0 HD 186791 K3II 1.51 –3.18 3.8 sb 4210 2.0 0.0 0.6 HD 186927 K0II-III 1.07 –21.79 1.0 – 4900 2.0 0.0 <0.4 HD 189276 K5II-III 1.58 3.79 1.7 – 3900 2.0 –0.1 <0.0 HD 190147 K1II-III 1.12 –1.06 1.0 – 4610 2.4 –0.2 <0.0 HD 192004 K3II-III 1.40 –19.99 3.4 – 4200 1.4 0.0 <0.0 HD 193092 K5II 1.65 –20.48 5.4 sb 4200 2.0 0.0 0.8 HD 193217 K4II 1.63 –19.02 3.4 – 4000 2.0 0.0 0.0 HD 195295∗ F5II 0.40 –17.91 9.5 – 6600 3.0 0.0 <1.5 HD 195432 G0II 0.64 –24.85 12.8 – 5100 2.0 0.3 <0.4 HD 196321 K5II 1.61 –9.69 1.9 – 3800 2.0 –0.2 <0.0 HD 197177∗ G8II 0.87 –26.21 1.7 – 5150 2.3 0.0 0.9 HD 199098 K0II 1.09 –29.49 10.7 – 4760 2.0 –0.4 1.0 HD 199612 G8II-III 1.05 –19.04 1.3 sb 4800 2.0 –0.3 <0.0 HD 201251 K4II 1.57 –26.83 6.3 sb 3800 2.0 0.0 <0.0 HD 202109 G8II-III 0.99 19.17 1.0 sb 4990 2.0 –0.1 <0.4 HD 204509 F4II 0.38 –22.66 19.1 – 6700 3.0 0.1 2.9 HD 205603 G8II 0.94 –6.49 1.0 – 4950 2.0 –0.3 0.8 HD 206731 G8II 1.00 1.45 5.2 – 4970 2.0 –0.3 <0.4 HD 210807 G7II-III 0.92 –16.66 6.5 – 5000 2.2 –0.1 <0.4 HD 211300 K0II-III 1.01 –3.27 1.0 – 5000 2.0 0.0 <0.4 HD 214567∗ G8II 0.93 –18.80 1.0 sb 5100 2.5 –0.4 <0.4 HD 216219 G0II 0.65 –7.46 1.0 sb 5700 3.3 –0.4 <0.7 HD 216756∗ F5II 0.40 –28.32 12.3 – 6800 3.7 0.0 3.1 HD 217673 K2II 1.50 –6.46 3.2 – 4400 2.0 0.0 <0.0 HD 218043 F4II 0.40 –10.46 20.1 – 6800 3.0 0.1 2.5 HD 218356 K0II 1.29 –27.71 4.4 sb 4400 1.8 –0.1 <0.0 HD 220102 F5II 0.60 –30.09 7.7 sb 6000 3.0 –0.5 <1.1 HD 220369 K3II 1.68 –10.77 3.2 – 3800 2.0 0.0 0.1 HD 221661 G8II 0.99 7.91 <1.0 – 5100 2.0 0.0 <0.4 HD 223173 K3II 1.63 –5.40 4.2 – 3800 2.0 0.0 <0.0 HD 224870 G7II-III 0.97 –20.31 6.8 – 5100 2.0 -0.1 0.9 HD 225292 G8II 0.95 13.00 <1.0 sb 5040 2.0 –0.4 <0.4